Many wireless devices such as smartphones and tablet computers are capable of wireless communication with other devices using wireless communication signals of different technologies or protocols including, for example, wireless local area network (WLAN) signals, BLUETOOTH® (BT or Bluetooth) signals, near field communication (NFC) signals, and cellular signals such as long term evolution (LTE) signals. Many WLAN and Bluetooth signals operate in the same portion of the ISM band (e.g., between approximately 2.4 GHz and 2.48 GHz), and some LTE signals operate in the range of 2.5 GHz. As a result, the transmission of WLAN, Bluetooth, and/or LTE signals from one wireless device may interfere with the reception of wireless by another wireless device. Further, many household appliances (e.g., cordless phones and microwave ovens) operating in the ISM band may cause additional interference in the reception of wireless communication signals.
Interference resulting from many devices operating in the same (or similar) portions of the ISM band may present challenges for a wireless device when detecting communication signals having a relatively narrow bandwidth in the presence of other signals, noise, and/or interference having a relatively wide bandwidth. For example, while Bluetooth signals are typically transmitted on channels having a bandwidth between approximately 1 MHz and 2 MHz, Wi-Fi signals may be transmitted on channels having bandwidths ranging from approximately 20 MHz to approximately 160 MHz. More specifically, interference resulting from many devices transmitting signals (or radiating energy) in the same portion of the ISM band may result in false signal detection for receivers employing simple energy detection techniques. Although receivers may be designed to detect, acquire, and demodulate narrow band signals in the presence of wide-band interference, such receivers may consume significant amounts of power and yet still be susceptible to instances of false signal detection. It would therefore be desirable to reduce the instances of false signal detection in wireless devices and/or to reduce the power consumption associated with detecting narrow band signals in the presence of wide-band interference.